The ABCs of English & Metric Pin Gages

A GO gage is used to check the lower limit of a hole. A NOGO gage is used to check the upper limit of a hole. If the GO gage enters the hole and the NOGO gage is unable to enter, the design specifications of the hole have been met.

Uses – for precision GO/NOGO measuring of hole sizes and depths, checking hole location and distance, and setting micrometers. All gages are uniformly 2″ long with ground ends, allowing you to use both ends for increased gage life. Gages are Carbon Chrome Alloy Steel (grade 52100 bearing quality steel) and heat treated to a 60-62 Rockwell C hardness. All of our products come with a Certificate of Class Conformance, traceable to NIST (National Institute for Standards Technology). The size and “+” (GO) or “-” (NOGO) are laser etched with a Meyer Exclusive Serial Number feature to ensure traceability on your shop floor on all gages that are .061″ and larger.

These class z gages have an inch tolerance of .0001″ and a metric tolerance of .0025mm. They are one half the deviation of the ZZ for a better fit. (Note diameters above .8250″ or 20.96mm tolerance increases, see gage makers tolerance chart)

These gages have an inch tolerance of .00002″ and a metric tolerance of .0005mm. They are one half of the deviation of the X. Great for your most critical needs. (Note diameters above .8250″ or 20.96mm tolerance increases, see gage makers tolerance chart)

This is bearing quality, Carbon Chrome Alloy Steel, heat treated to 60-62 Rockwell C hardness and is considered the preferred material for the highest quality plug gages.

NIST, the National Institute of Standards and Technology, is a federal agency that develops and promotes measurement, standards, and technology to enhance economic security and quality of life. NIST’s work helps to ensure the reliability of materials, products, and processes, as well as the accuracy of measurements. This is achieved through research, testing, and the development of standards and guidelines.